I believe Bitcoin and Ethereum are the best choices right now as the market is at such a low and these coins are the best for risky investment right now. Bitcoin because being the pioneer of the cryptos, the coin is the most widely accepted coin in the market and is also considered as a brand for other cryptos.
Ethereum has proved to be a great potential coin and is now being accepted by major companies like Microsoft, Intel, JP Morgan. Since its origin in 2015, the coin has shown major increase in its market capital and hence has shown a significant rise by 1100%. Also, its secure blockchain makes transactions much more secure.
You can expect good returns from these coins.